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A study by IT research company Nucleus Research shows that company productivity drops by an average of 1.5 percent when employees are allowed to use Facebook on the job. According to Sharon Gaudin of Computerworld, 77 percent of the 237 employees surveyed for the study access their Facebook account during the workday, and 87 percent "had no clear business reason for using the site."

In a statement directed at employers, Rebecca Wettemann, the vice president of research at Nucleus Research, said, "While it won't make you popular, restricting Facebook can reclaim lost productivity. If your profitability is say 2%, this could be the difference between staying open or closing shop."

However, previous studies have indicated that managers who cut off access to social networking tools may lose staff.